William barton eddison



Cn E. RICHARDSON, W. B. EDDSSN AND H. L, READ.

METHOD F BUHNiNG EXPiSVE GASEOUS MIXTUHES APPLCANON HLED SEPLZB |91]-Patented July 1, 1919. 2 SHEETS-SHEET l c. E. mcHAansem, w. a. www ANDH1. READ.

APHICATION FILED SEP?i 29. 19| I.

Patented July l, 1919.

2 SHEETS--SHEE 2.

oritire suitable means,

T OFFICE.

METHOD OF BURNING EXPLOSIVE GASEOUS MIXTURES.

Specication of Letters Patent.

atented July 1 1919.

Original application tiled November 23, 1916, Serial No. 133,086.Divided and this application filed September 29, 1917. Serial No.193,982.

To 11H w/toni it may concer/lz.'

lle it known that we, Cuantas E. Rien- Aunisex` WILLIAM' lxu'roNllnmsox, and lluxnv L, Rican, citizens of the United States. residing,respectively, at New York city` county of New York, and State of NewYork; Irvington` Vestchester county, New York. and New York City, countyof Kings. New York, have invented certain new and useful Improvements inMethods of Burning- Explosive Gaseous Mixtures, fully described andrepresented in the following specification and the accompanyingdrawings, forming a part of the same.

This invention relates to a method of burning explosive gaseousmixtures, and aims generally to reduce the pressure under which it isnecessary to supply the explosive mixture to the discharge tubes ornozales, to increase the range of heat production or amount of mixtureburned with a limited maximum supply pressure, and to avoid the dangerof backflashing through the supply passages under any operatingconditions but especially when operating with mixture supplied underrelatively loW pressures` and also to maintain the pressurerapacitycharacteristic of the burner tube or nozzle under varying supplypressures, this being desirable with some types of mixture supply meansin order that the proportions of fuel and combustion supporting;r Agasin the mixture shall be maintained constant.

The invention has to do with the method of combustion in whichcontinuous and local- 4ized combustion of an explosive gaseous mixtureis secured by causing the mixture to flow from a discharge passage ororifice with a velocity greater than the rate of propagation of'inflammation of the" mixture in order 'to prevent baekflashing, and theneausingr the mixture to spread out with rapid reduction of its flowvelocity and burning;r the mixture where its flow velocity equals therate pf propagation of infiammation of the mixture. The spreading of themixture may be caused by baffling means consisting of a porous andpermeable bed of suitable highly refractory material, or other locatedelose to the discharge so that the'stream is caused to spreadimmediately as it leaves the orifice, or the mixture may be permitted toflow from the orifice as an unconfined stream Whichimplages against abattling means spaced off' at a suitable distance from the dischargeori- `ce. or the rapid spreading of the mixture may be caused in otherways.

By such Vcontinuous and localized combustion of explosive gaseousmixtures, extremely high temperatures are developed, and variouspractical difficulties have been experienced due to the heating of theWalls of' the mixture discharge passage or orifice. lt is found that theWalls of' the discharge passage or orifice become heated, combustion ofa portion of the flowing mixture tends to take place Within the mouth oithe orifice and to gradually Work back along the walls of the orifice ordischarge passage while the main portion of the mixture is flowing on,unburned, to be consumed at the surface or place Where. its flowvelocity has been reduced to the rate of' propagation of inflammation.This baek-creeping of combustion, which is a totally different thingfrom back-flashing" through the body of the stream of mixture, probablyresults from the presence of' a relatively slow moving thin layer orfilm of mixture against the walls of the disci-large passage due to thefrietional resistance exerted by the walls on the mixture flowing pastthem. If the edge of' the discharge orifice becomes heated to a`sufficient temperature, probably a temperature somewhat above theigmtion temperature of the mixture, this relatively slow moving lm ofmixture becomes ignited at such point and combustion then travelsbackward alongr the walls for a distance and at a rate depending uponthe temperature of the Walls and the velocity at which -the mixture isflowing through the passage. lVith increase in flow velocity of themixture, the thickness of the relatively slow moving wall film isreduced and the cooling effect of the stream of' mixture on such filmand on the walls of the passage themselves increases, so that 'thehacli-creeping,r tendency decreases with such increase in flowvelocity-of the mixture` and with a sufficiently' high flow velocitybaci-.creeping may be stopped and combustion within the dischargepassage or orifice entirely prevented. Prevention of suoli back-creeping1n tlns way, however, means that contmued operation of the apparatusrequires a relatively high mixture supply pressure.

This back-creeping of combustion along the walls of the supply passageis objectionable for a number of reasons: It causes i more or less rapiddeterioration of the Walls of the discharge passages according to thematerial of which they are formed; by heatin the stream of mixtureflowing throng the passage, it causes af development of back pressure orresistance to iiow, which reduces the velocity with which the mixture isdischarged under a given supply pressure, and which is objectionablewith some types of means for supplying the mixture because of its effectin changing the proportions of the constituent gases in the mixture; andit causes ignition and explosion of the slower moving mixture iii supplypassages or chambers, when the backcreeping reaches such a passage orchamber. By reducing the velocity of discharuc,

the development. of back-pressure or resistance to flow resulting fromthe heating of the mixture limits the reduction of supply pressure`under which the apparatus will operate and restricts the range ofopera.- tion under a given maximum supply pressure.

It is desirable, in order to reduce the resistance to flow of themixture, that the discharge passage through which the mixture is causedto move with excess velocity to preven't4 backflashing, he relativelyshort, the mixture being supplied to such passage through a largcpassage in which the flow velocity is relatively lower. It is alsodcsirable that the mixture be discharged through a short passage ororifice of such forni that flow of mixture therethrough under varyinpressures shall var according to the Howaw of orifices, and tiat iperesistance as a-controllin factor on t e flow of the mixture be avoided.With such a short discharge passage or orifice, the danger of ignitionof the mixture in the larger portion of the passage and backfiashintherethrough is, of course, greatly increase both from the back-cree ingof combustion along the walls of the discharge passage or orifice, andalso'by the conduction ofheat through the walls themselves.

It is the object of the present invention to avoid such back-creeping ofcombustion of any part of the mixture within the discharge passage ororifice even with a comparatively low mixture flow velocity, and thisresult is secured according to the resent invention by maintaining theWal s of the discharge orice or passage at a tempcrature which issubstantially lower than the ignition temperature of the mixture, bycausing the heat reaching the nozzle, and which would otherwiseaccumulate and raise the walls of the discharge passage or orificereceive heat either from the furnace clianibei' or from the, furnacewall or from other parts of the nozzle to have suflicient heatconducting capacity to conduct the heat rcceived with suflicientrapidity to maintain the walls of the mixture passage at the desii'cdlou' temperature, and is provided with fins or other means providingsuiiicient eX- tcnded surface for the discharge of heat to theatmosphere or with other means for takiupfrom it the heat conductedbackward through its body portion. Whether or not the bodyv of thcnozzle of sufficient mass is depended on to conduct the heat from theexposed end of thc nozzle back to the dissipitatingnieans, the walls ofthe mixture discharge passage or orifice should be of material of highheat conductivity, such as iron or other suitable metal. As suchinaterial not only conducts heat rapidly, but also rapidly absorbs heat,the nozzle is so far as possible protected from direct access of -heatby a covering of material of relatively low heat conductivity, usually apart of the furnace wal] of brick, cement or other refractory material,in which the nozzle is set. Such material, however, because of its lowheat conductivity, becomes very highly heated under the intense heat ofthe coinbustion of the explosive mixture, the Whole refractory wall of afurnace chamber usually becoming more or less highly incandescent.Contact of any part of such material, therefore, with theJ stream ofmixture issuing from the nozzle orifice would result in ignition of themixture at the edge of the orifice, and to avoid this, a part of themetal of'the nozzle nose immediately surrounding the orifice is leftuncovered, the width of such exposed portion of metal bein suffi- `cientto prevent contact of the issuing stream of mixture with, and ignitionthereof by, the surrounding refractory material of the furnace wall bywhich the vmain portion of the nozzle is protected.

'l'he accompanying drawings illustrate an approved forni of apparatus bywhich the method may be practised, such ap aratus being claimed in myoriginal application Serial No. 133,086, tiled November 23, 1916, Patent No. 1,242,114, granted October 2, 1917. In said dranY- gez- Figurel is a central sectional View of a soft metal melting furnace for`burning exmoana@ Fig. 2 is :iii cnlzirgril piirt ol' oliv ol' the zlilslShown iii Figi. l :ind iiddizii'viil poriom o( llii l'nriizno walls;

Fig. il in nii oiilniilix ond vie-w oi' iiozzcli-h, uliown iii lfigu, l:ind :l:

lli-fi-iriiig to thv drawings, und lir i lo Fim. 1 1! :ind 8, iluxfui-num drin-Niro Ynliowii i-oiiipi'iuvs, :i lioioiii willi or floor l()iiiiil sido mills l1 of liricliw work, iljiilii'iili wiill il livinginclogiiil within iin onlinr iiiotl i'iiniiiir 12 with imiiitiriiicdiiito si'iiiov lieiiii'fioii tliia iiiiliil iiiiil tliirlil-irl: filled with lie-nt iiiwiiliil ing iiiiiliei'iiil 113, lSuch :ispowdoriul niko-vol.

(iii-rire! h v :i suitiililo support oii the iop oi" iliisidir mills;11. in :i niclliniir poi'. 1.3 which oxivnds down into tho furnace0liiiiiiliviliilwvoii the side walls.

'lliv iixplosii'c giinioiifi niixiiii io lio liiii'iivil iniliscl'izirged from ii pliiriiliy of discharge tubes or nozzles 20. ofwhich two :iro shown iii so 'tion iii the drawings, iiiouiitn ed iii tlmnido wall Til :ind svt o dirigir, liii jvi or stri-nin o mixture issuingiili-fiifroiii zigiiiiislJ :i kuitsililir liiillling infini,` hy whichthiY ,luixlui-u is unused fo spifaeiid our wii i'iipiil rodiiiiion ofits flow Vi'loiitli'. in liv .fui'iiiici sliowii the liiillling'iiiiaiiin` im spnrigil oil' from thv nozzles so that ilii issuingntrwiim` of mixture rire piriiilttil go ii'iii'ffl from this iiozzlis totliiliiillliiig; Iiiiiiiis iis niiioiiliiioil stiroiiiiis, und shown tholiiiilliii;r moans i'oiisists of :i heil or beds 2l forniiul of pincesof refractory iiiiituriiil iii'i-:iiigvd with tho surface of thv hifl inSiii'zililiy r0liilion to the dowiii'i'iiidly dirwiilil uti-mini nl'mixture so iliat tho Siri-,inn will lili iiiiillvil :ind iiiiisiil iospread oui` iii tlii- (lffsirril iii-:iiiiior. Such ii lioil will licporousi sind por iiiiiiilili: :nid will have the iidi'iiiiizigrii of'por milling tlicproducts of voiiihiislioii lo puni; through it iiiiilesi'iipi tlieril'roiii lioi'oiiil iluj phil-ii wliorv coii'iliiistioiinikon pliicp. und tho Qoiiiliiihlioii muy liilo nlziiiy :it thvniiii'iii-i -il' lliiluid or within tho lied. ilcii'ordiiiig to llioHizo of thi stream of mixture und thi iiloi'iij," with wliiili itSirikin the' hod,

l'iiiiiiiiif of this liiiiil iiiiiy lii oi" :iiiiY diniroil liiipo iiilioiizonliil Siiiliou. rlliioiii1 shown i ii i'ii'iiiliir l'iiriiiiifv`rlii3 minfin-iL dini-luogo iiozxliw` of wliiili llii'i'iinni' lili :ini`ilvsiiid or iioiiii'vd niiiiilwi. liiiiilii' iringi'il iwiiliiillli inthe o viiiidi'ioil woll l1.

primeiro fo i'iiiihi iliil iiiifiiiiro to lio llii'lmi'giil if illi :ii'ilollty iii oxi'cw: olV #in riili ol' pii'ipriiliilion oi"iiilliiiiiiiiiitioii olY thu inizi" :iiir iiilulilil nourri or iii' imi'Aa' shown, si mixing miei-f iiru from suitable roe-zins.

'iii tlm loriii ol' iol' in providwl l'or :supplying :iii i.\plo.\i\'iiiiixnro of liiol gfiis und nir. ilu' gus living i-:lipplii'sil to iliixinici-for nomli' 2. iiiidoi niiiiiilili; prusmiro iinil :iiil livingliziwii iiiio l'lic i-oiiiliiiiing' iuliiA El? of [,liv inji-clor laithi- ;zis ii-L :mil ihn gus ziiiil :iir [lion paissiiiig i'irniigli henoir-li ol iliiin ioi-ioi :ind iliioiigh lli@ disuliiii'go or prossimivom" T lo :i .'npply pipi' or iiiziiiil'old 2H from whioli lii'iiiniion25? loud to thv .sii'iriil iiolfizlw 13N. 'lifr injector should liodosigjiiid. :ind iliinos-:xls iiiiil ooiiihiiiiiiif ruhe soi iii propri'rifliitii'o position, :in h i adjusting iitlivr oni, to ffiippliy iiinixliii'ij containing tho gus :iiiil iiir iii Suitable proportions.iiiid lliiri should riiiicli thi: iiijoctor iinilir Huliigimit promu@ toviiiiso thil iiiixtiiri` is nippliiil to flic iiiixzlo@4 to llowiilii'oiigli the dioiliiiigi oriliiin ni thi nov/lim` with :i wloiziyiii @was of llio riito of propagation of lliiniithrough the iiiixtiiii.The` iiiiiiiifold 2H :uid supply liriiiii'lis 2l? should liv largoiiioiigli lo pii'niit thi` mixture lo :now lliii'oiii willi niiili(yoiiipiirzitivvly low iifloiiiy :in to so ifiiii ii substantiallyiiiiiforni lsuppl)l of iiiix inria to :ill of the iiozzlvs. und tozivoid priis- :wiiiv losnvs dni lo pipi! fiii'flon.

Tho nozzles 20 uri foi'iiiod iiii'li willi :i lioi'i or piisszig'il $5.3u iliiiiliiigir through iliiI holly of ilu` iioxzlo of :i sii/.o wlilvliis inout ili-r`iriilily L |ilistiiiiiiiilly gri'i-:itii' lliiiii thvwif/.o o1" llii, iliwlizirgo orifice. :ind thi` piissiigo lli'- pirsdown :it ihr i'roiit or dinrliiirgzi iiiil olE llio now/:lo undloi-minutos iii :i ruslrii-lid liorl ilisrliiirgo pzissiigo oi'orili'i'il 3H wliii'h douiriilily lisis piirzillol wiillsi` for iiliiigtli unlI4 lli-ioni lo muso thi` iiiixiiiii to liil dini-liiirgod iisolid lii-l or slrviini. Thiiiozzli is foriiiid ol miitvriiil ollliig'li llioi'- iiiiil i-oiiilucliviiy, such nu wwf-iron or ollior`viiiiililii iiiiiiil, :ind in' iiiiiilo ol' 4iillli-iont.ifixiuwniliiioii or iiiiiml so that :ill portil thoroo' @hull huw lioriiiliiiriil honi voiidui'iingl wipziiiiy l'fir i'iiirliinif :iw-iv :itthe iio i-.\:ii' iiilu :ill liiiil washing suoli pzirt. 1t is svt inlii` l'iiriiiiifv wiill iiiiil pi'otii'tild liv lliil wiill fiomdii-ovl. zii/'ross ol' tho. furiiiii'o liiiil. i-xiipl for ii liinil'iilportion dl" ilo` di-i-liziri vnd or nono :id izu'i'iii flic oi'iliio.The` iiid of thu iio'fizliis iiiost'` ilisirzilily Tapi-rod :inluliowii. :mil hun :i liliiiit @diro lo pi'oviilo :i lli-il mirroir:iiiiiiiliii l'iivo 2ST :ihout iliil oiilii-ii io lio lil'iiiiiioviii'il :ind ixpowd To thil vfiirliiiii liil.

lil i deniriilili lo liiiw [liv nozzle pi'ol'eifi'i-d ,io l'zii :inponsilili i'i'oiii dirii'liiii'iss of fliriiiii'o lief-Lil` lioili forthe piii'pi'isi; ol' liv-ping lowii lo ii iiiiniiiiiini the loss oflient;` ilirough lio iioxzlv wills` iiiiil to :Wold unduly7 iiiiiai thesim ol' ilic` nozzln lo giro it flic ,iiifvihsiiri hiiif mirryiiigmpziiiihy. flii llic iiir iiiiil` ii` is iiiii'ifisiii'y, :is poinliidout huil *lliure Sliiill he Sonie oxteiit, of iiiiiiiil iiiion tho odgeof the diuirliiirgo oriii'v ox posed to direct iiiicess of heat from thofurnat-e chamber, in order to prevent` contact with the stream ofmixture of any material of relatively low heat conductivity forming partof the furnace wall. Because of its low heat-carrying capacity, thercfractpry material ot' the furnace wall, under the intense heatdeveloped, becomes extremely hot, usually incandescent. The eiqiosureVof any suflit-lenty extentI ot' the metal of the nozzle about the edgeof the orifice prevents Contact of such incandescent" material with themixture and avoids the ignition of the mixture at the edge of theorifice with increase in temperature at this point and increasedtendency to baclcereeping which would result from such Contact. p t

The exact width or extent of metal left uncovered at, the nose of thenozzle is not particularly important, provided it is sutlirient tosecure the desired result, but in order to avoid loss ol heat and thenecessity of providing for the carrying away of such excessive amount otheat, it is most dcsirably not much wider than is necessary to protectthe mixture from the incandescent material.

ie have usually found it desirable to Scl) the nose of the nozzle slihtly back from the face of the fin-nace wel in a small recess formed inthe face of the wall, with the nose of the nozzle extending somewhatinto the recess, and then partly filling in the recess about the nozzlenose with a suitable refractory cement, as iiulicated at 40, having thecement extend not beyond the outer edge of the annular face at the end.of the nozzle and forming it to flare suitably awayv from the path ofthe mixture stream. The cement should be carefully placed to Jforni atight joint with the end of the nozzle so that it may not only protectthe same from direct access of heat, but also by sealing the spacebetween the nozzle and the hriekwork prevent the hot furnace gases fromflowing in around the nozzle, although this is not necessary providedthe nozzle is otherwise suit ably sealed iu the wall so as to preventthe flow of the furnace gases past it. The nozzle is desirably formedwith a tapering nose as shown having near its discharge end projections41 of suitable form to provide a hold for the cement 40.

For taking from the nozzle the heat conducted front its exposed portionsbackward through its body portion, the nozzle is provided with hcatdissipating fins 42 formed on its rear end outside the furnace wall,such fins providing extended surfaces of sufficient extentto dischargeto the atmosphere all the heat reaching them through the body of thenozzle with suicient, rapidity to prevent such mumulation of heat4 inany part of the nozzle as would result in an undue increase intelnperamre of any such part. The Fins may be of any suitable form. Flatannula: tapering tins of about the proportionate size shown in thedrawings on nozzles made ot' cast-iron have been found entirelysatisfactory under various conditions of operations and make theprovision of special means, such as means providing a circulating Huid'for carrying away heat from the nozzle, wholly unnecessary. The nozzlemay be secured to the outer casing of the furnace wall by means of aplate 43 formed on the nozzle, as shown, this plate also serving as anadditional heat dissipating means.

Fig. 4 shows a. form of water-cooled nozzle consisting of acomparatively thin-Walled mixture tube 50 provided with a tapered nosepiece 51 formed to provide a restricted discharge orilice, and a metalcasing 52 extending about the tube 50 and connected with the edges ofthe nose piece 51, the space between the mixture tube and the casingbeing divided by a partition tube 53 which ends short of the front endof the casing so as to provide concentric supply and return flowpassages for water or other cooling fluid which is supplied anddischarged through pipes 55 and 5G. This jacketed nozzle may be set inthe furnace wall in substantially the same manner as the air-coolednozzle shown in Figs, l to 3, the front, end of the nozzle beingprotected more or less from direct access of furnace heat by aprotecting covering formed by a filling of cement or other part of thefurnace wall, such protecting covering ending short ot the edge of thedischarge orifice as shown an for the purposes hereinbefore described,

lt will be understood that by the term explosive gaseous mixture usedherein is meant a mixture of a suitable combustion supp yrting gas,either oxygen alone or air or other oxygen-containing gas, withcombustible matter iu a gaseous or other finely divided state in properproportions` that is, in proportions such that the mixture will have theproperty of (sclffpropagation of inflammation. For producing the highesttempe1'ature,the oxygen should be undiluted and the mixture shouldcontain oxygen and combustible matter in chemical combining proportionsat the time of combustion; but there may be an excess of either thecomlntstible matter or the combustion supporting gas within the limitswhich determine the property of self-propagation. The mixture may bevaried in this respect according to the desired character of theproducts of combustion, that is, whether it is desired that the roductsshall be neutral, oxidizingr or reduring. Also, the mixture may ofcourse contain neutral gas such as nitrogen ,`carbon dioxid or watervapor, so long as the amount of such neutral gas is not sufficient tomake the mixture nonexplosive.

What is claimed is:

*1, The method of burning explosive a BQIS mixtures. which comprise'-oisrha ing a stream of the mixture from a discharge orifice with avelocity greater than the rate of propagation of inflammation of themixture and causing the stream of mixturc 'to spread out with rapidreduction of its flow velocity, burning the mixture where its flowvelocity is reduced to the rate of propagation of inflammation, andmaintaining the temperature of the walls of the discharge orificesubstantially lower than the ignition temperature of the mixture.

2. The method of burning explosive gaseous mixtures, which comprisesdischarging-a stream of the mixture from a discharge orifice with avelocity greater than the rate of propagation of inflammation of themixture andcausing the stream of mixture to sprad'out with rapidreduction of its flow velocity, burning the mixture Where its flowvelocity is reduced to the rate of propagation of inflammation, andmaintaining the temperature of the Walls of the discharge orificesubstantially lower than the ignltion temperature of the mixture bywithdrawing heat from the Walls of the orilice with suilicient rapidityto prevent increase in temperature of the Walls above the desiredmaximum.

3. The method of burning explosive gascous mixtures, which comprisesdischarging a stream of the mixture from a discharge orifice with avelocity greater than the rate of propagation of inflammation of themixture and causing the stream of mixture to spread out with rapidreduction of its flow velocity, burning the mixture Where its flowvelocity is reduced to the rate of propagation of inflammation, andmaintaining the temperature of the walls of the discharge orificesubstantially lower than the ignition temperature of the mixture bylimiting thc access of heat to the orifice and by withdrawing heat fromthe Walls of the orifice with sucient rapidity to prevent increase intemperature of the walls above the desired maximum.

4. The method of burning explosive gaseous mixture', which comprisessupplying the mixture to a discharge nozzle under pressure suilicient tocause the mixture to be discharged from the nozzle with a velocitygreater than the rate of pro agation of inflammation of the mixture, baing the stream of mixture issuing from the nozzie to cause the same tospread out with rapid reduction of its flow velocity, burning themixture, and maintainin the temgerature of the walls of the dise argcorice of the nozzle substantially lower than the ignition temperature ofthe mixture.

5. The method of producing heat, which consists in combining fuel in afinely divided state with a combustion supporting gas in proportions toform an explosive gaseous mixture, supplying the mixture as it is formedto a discharge nozzle under sulficient pressure to cause a stream of themixture to be discharged from the nozzle with a velocit greater than therate of propagation o inflammation of the mixture, baffling the streamof mixture issuing from the nozzle to cause the same to spread out withrapid reduction of its flow velocity, burning the mixture, andmaintaining the temperature of the Walls of the discharge orifice of thenozzle substantially lower than the ignition temperature of the mixture.

In testimony whereof, we have hereunto set our hands, in the presence oftwo subscribing witnesses.

CHARLES E. RICHARDSON. W'ILLIAM BARTON EDDISON. HENRY L. READ.

lVituesses:

EUGENE E. BARCQUIN, ROBERT A. CRUMM.

